Pad attaching means for rubbing machines and the like



March 15, 1949. G. H. EKsTRoM 2,454,296

PAD ATTACHING MEANS FOR RUBBING MACHINES AND THE LIKE Filed Nov. 26, 1947 Patented Mar. 15, 1949 PAD ATTACHING MEANS FOR RUBBING MACHINES AND THE LIKE Gustaf H. Ekstrom, Rockford, Ill., assignor to Sundstrand Machine Tool Co., Rockford, Ill., a corporation of Illinois Application November 26, 1947, Serial No. 788,172

This invention relates to pad attaching means for rubbing machines and the like, and more particularly to means for so attaching a pad to the shoe of a rubbing machine that when worn out the pad may be discarded and a new pad applied without throwing away valuable material with the pad.

In rubbing shoe pads as used prior to my nvention, metal strips, threaded pins, etc., were xed in position in the pad in such manner that when the pad was worn out and in condition to be discarded it was necessary to throw such other valuable parts away with the pad. This involved considerable waste of valuable material as well as added expense in forming and apply- A ing such pads to the shoe. In the present invention I have eliminated this waste of material Iwith its added expense, and have provided a pad in which the means for clamping the pad to the shoe is not thrown away with a discarded pad, but is retained for use with a new pad when the latter is applied to the shoe. The pad of the present invention may be used with or without additional strips or sheets of abrasive paper, so that heavy duty rubbing may be accomplished when such abrasive sheets or strips are applied over the pad, and for polishing and light rubbing purposes the pad may be used without said abrasive sheets or strips.

Among the objects of my invention are: to provide a novel and improved pad for rubbing machine shoes; to provide novel pad attaching means for rubbing machine shoes; to provide means for attaching a felt pad to a rubbing shoe in such manner that when worn out it may be removed and thrown away without the loss of more or less expensive parts within the pad; to provide a pad of the type referred to having a clamping strip slidable into a slot in the pad for clamping the pad to a rubbing shoe and which pad is removable from said clamping strip by being pulled edgewise away from the shoe when the clamping means is loosened so that the clamping means may be used continuously with as many new pads as may be desired to successively apply to the shoe; to provide a felt pad for rubbing shoes having laterally extending T-shaped slots, and anchoring means positioned in the slot to clamp the pad to the shoe; and such further objects, advantages and capabilities inherently possessed by my invention, as will later more fully appear.

Otherobjects will become readily apparent from the following detailed description taken 11 Claims. (Cl. 51--189) 2 in connection with the accompanying dra-wing in which:

Fig. l is a top plan view in reduced size of a shoe of a rubbing machine, and having attached thereto a pad embodying my invention.

Fig. 2 is an edge View looking toward the bottom side of Fig. l.

Fig. 3 is a bottom plan view of the rubbing shoe omitting the pad therefrom and showing the anchor strips which will clamp the pad to the shoe when the pad is applied thereto.

Fig. 4 is a fragmentary enlarged top plan view, partly broken away, looking at the upper` face of the pad embodying my invention.

Fig. 5 is a vertical transverse section on the line 5 5 of Fig. 1.

While my invention further resides in the combination, construction and arrangement of parts illustrated in the accompanying drawing, I have shown therein for illustrative purposes only, a preferred embodiment, and lwish it understood that the same is susceptible of modification and change without departing from the spirit and scope of the appended claims. In the form shown in the drawing, I have i1- lustrated a pad l secured to a body plate 2 of the shoe of a rubbing machine. Clamped by clamping jaws 3 and 4 at the respective ends of the shoe are a plurality of sheets or strips 5 of abrasive material passing around the ends and the bottom face of the pad and held taut thereover. While any type of abrasive sheet clamping means may be used, I have shown for illustrative purposes only, abrasive sheet clamping means of the general type shown in the co-pending application of Charles D. McCarthy, iiled May 17, 1946, Serial No. 670,469. Other forms of such abrasive sheet clamping means however may be used as desired. Without going into details, such clamping means comprises generally a pivoted clamping jaw (3 or 4) with a lever 6 pivoted in a pair of upstanding arms 'l and 8, the vdownwardly bent portion of lever carrying a roller 8 rolling upon a bowed spring member 9 to clamp the jaw against the abrasive strips when the lever 5 is pushed downwardly. This downward movement of lever 6 moves the roller 8 to push downwardly on the bowed spring 9 to in turn force the clamping edge of jaw 3 downwardly to tightly grip the ends of the strips of sandpaper or other abrasive sheets against the end and bottom faces of the pad.

While only one end of the upper face of the pad I is shown in Fig. 4 it will be understood in Fig. 2 that the opposite end of the p ad is simif' larly formed. Only one end of this portion of the pad will be described, it being understood that the slots in the other end portion of the pad will be identical to the one now being described. Referring to Figs. 2 and 4 there is provided adjacent each end of the pad a laterally extending T-shaped slot comprising the. bottom ywide portion Ill formed within the body of the pad and extending laterally therethrough from one side edge of the pad to the other. The pad, above the bottom portionl II) of the slot is formed centrally of slot III- and extending from edge to edge of the front face of the pad with a slit I I which connects slot I'Il with said upper: face. The walls forming the edges.- of; slit II near the ends of this slit are cut away at I2 and I3, to jointly form openings I4 only one of which is seen in Fig. 4, it being understood that the other one of these openings would fall in the broken away portion in the lower left hand portion of Fig. 4. The purpose of these openings will ce later more fully explained. It is thus seen that opening I and slit II jointly form a T-shaped slot, the portion I constituting the cross bar of the T and the slit II constituting the stem of the T.

For securing the pad to the body plate of the shoe I have provided a pair of anchor strips I and Itv which are preferably of thin metal and of a width and length as shown in Fig. 3. Fixed ad.- jacent each end of each of the anchor strips I5 and I6, by rivet heads or the like I'I pressedy over against the bottom face of these strips, is an upstanding pin I8, each of which pins is screw threaded at its upper end portion I9 and for a desired portion of its length, to threadably receive the complemental nuts 20. By means. of these nuts the` anchor strips I5i and I6 may be tightened toward` the body plate 2- of the shoe or loosened with respect thereto as desired. These strips I5 and I I5 are of approximately the size and shape of the bottom portion IIJ of they 'rf-shaped slot, so that when these strips are loosened to stand a distance away from said' body plate the pad may be slipped thereover by moving the edge of the pad laterally with relation to ther body plate, so that the strips will be forced into openings I0. At the same time the upstanding threaded pins I8 will bel forced along slits Hi, and when the pad has reachedy the positionv to substantially register with the outline ofl the body plate the opstanding pins- I8 willv be' re.- spectively seated in the openings I4. Byf seating the pins in openings |54 whenl the padis in registering position with the body plate, any tendency of the pins to distort andbuckle: the edges of slit il will be prevented, because of the diameter of said openings I4 being at least equal to the diameter of these pins. From the above it will be seen that whenv the padv is moved laterally with relation to the shoe,Y with the, anchor strips I5 and I6 seated in opening I0 of the'lishaped slot, a tightening of each of the four nuts 2i) will draw the anchor strips upwardly toward the body plate 2 so as to clamp the flanges of the pad on the two sides of the slit I I tightlyA against the bottom face of said body plate., This will-scf curely attach the pad to the. shoe, after which, if desired, any number of sheets or strips .of abrasive paper, cloth or the like 5, may be appliedover the ends and bottom face of the` padA and tightly clamped in position by theclamping jaws-3 andd.

When a lighter type of rubbingisi desired, such as light polishing and the. like,r the abrasive sheets 5 may be omitted andthepolishing done directly with the bottom face of the felt pad I. From this construction it will be seen that the anchor strips I 5 and I6 are not thrown away with the pad when the pad is discarded, but these anchor strips will be available for use with as many successive new pads as desired. In other words when removing the pad, from the shoe, all that is necessary is. to loosen they nuts 20 so as to loosen the' anchor strips in the T-shaped slots after which the pad may be pulled oliD edgewise and slid olf. of the anchor strips, permitting the latter tovv remain with the shoe. Or if desired the nuts 2U may be entirely removed from the threaded pinsy I8 and. the pad and the anchor strips pulledA awayA from the shoe, after which the anchor strips may be pulled out of the T-shaped slots. The width of the flanges 2l and 22 on the two sides of the slit I I is great enough to give ample clamping space when clamping the same between the anchor strips I5 and I6 and the lowerface ofthe body plate of the shoe when tightening the nuts 20a The felt of the pad I will have suiiicient exibility and resiliency to permit the pins I8 to be pulled through slit II when re;- moving the pad from the anchor strips, or when removing the anchor strips from the pad.

Having described my invention, I claim:

l. Pad: attaching means for rubbing machines and the like, comprising, a body plate adapted to be secured to a rubbing machine, a. felt pad having; a IT-shaped. slot extending transversely thereacrossl adjacent each end, the stem of 'the T of each ofsaid slots opening into one face of the pad and the crossr bars4 of thev slots being formedk in the body of the pad and having their ends opening at the side edges of the pad, a pair of an,- chor strips slidably positioned one ineach of said slots,l a projection extending from each-v of said anchor strips, said projections passing; through complemental openings in; the body plate, each of saidprojections passing through the: stem of its T-shaped slot, and means on said projections for pulling the anchor stripstoward the plate, for clamping the pad, to. the platel whereby a used pad may be. removedv by loosening the; pad clamping",y means and sliding, the pad laterally ol ci said anchor strips and anew pad may beapplied by.v the reverse operation. ontoV the same anchor strips.

2. Pad.attaching` means as. claimed in` claim I,

in, which the edgewalls forming the, stem of each of said? slots are cut away at oppositel points, to receive the respectivey projectionsv when the. pad is in position on the plate to prevent distortion o fsai'd edge Walls when the pad is secured to the plete. 34A felt pad for rubbing machines,y having. 'formedtherein to extendtransversely thereacross Aathin opening of'substantial widthopening atits ends in thev sidje edgesl of the pad, said pad alsohaving av narrow slot extending transversely across the pad and connecting with saidl open? 'i'ng whereby saidv opening` and slot. may receivel removableV fastening means for securing the pad' to a rubbing machine.

Vil A felt pad as claimed4A in claim 3', in which the edgewalls` of said slot arevformedwith' opiposi-tely positionectcut away portions to forman enlargement of the slot.

5'. A' pad for rubbing machines, having a body portion formedwith a. If-shapedf slot, the` cross part: of theT'be-ingin thebody of= the'bodyfportion, and the stem of theT connecting theI cross part: with aflatlface'ot the pad, said-f T-sh-aped slctopening atcneend in an: edge-ofI the body portion whereby to slidably receive a fastening member for attachment to a rubbing machine.

6. A pad as claimed in claim 5, including an anchor strip slidable into and removable from the cross part of the T-shaped slot, said anchor strip having a projection slidable into and out of the stem of said T-shaped slot.

7. A pad as claimed in claim 6, in which the stem of the T-shaped slot is formed with an enlargement to receive said projection when the anchor strip is in nal position in the cross part of the slot.

8. In combination in a rubbing shoe oi a rubbing machine, a body plate, a pad having adjacent one end a T-shaped slot formed therein, said slot having a cross portion in the body of the pad and a stem at right angles to the cross portion, said stem opening in one face of the pad, said T-shaped slot extending transversely across the pad and opening in the pad side edges, the walls of the stern of said slot having oppositely positioned cut-away portions, an anchor strip having a screw threaded pin xed thereto and extending substantially at right angles thereto, said strip being removably seated and endwise slidable in said cross portion of the T-shaped slot with the pin extending through said stem of the slot and being seated in said cut-away portions when the pad is in inal position, said pin extending through a hole in the plate, and a nut threaded onto the pin above the body plate to clamp the pad against the body plate, the pad being removable from the body plate by an edgewise pull when the nut is loosened, whereby a used pad may be removed from the anchor strip and discarded and a new pad slid over the same anchor strip and clamped thereby against the body plate.

9. In the combination claimed in claim 8, in which said pad is formed of felt, and two of said pins are xed to said anchor strip in spaced apart relation and similarly attached to the body plate.

10. In the combination claimed in claim 9, in which said pad is formed adjacent its opposite end with a T-shaped slot, an anchor strip, and threaded pins and nuts similar to those first mentioned, whereby said pad may be rmly clamped to the body plate adjacent both ends.

ll. In combination a metal body plate having a gripping jaw adjacent each end of its upper surface, a felt pad having adjacent each end a T-shaped slot in each of which slots that portion forming the cross of the T is within the body of the pad extending parallel with the plane of the upper face of the pad and that portion forming the stem of the T extends substantially at right angles to said cross portion and opens into the upper face of the pad, the walls of the stem portions of said slots having oppositely positioned cutaway portions at spaced apart positions in each of said stem portions, an elongated, thin, anchor strip slidably mounted in the cross portion of each of said T-shaped slots, a pair of threaded pins fixed in each of said strips and adapted to slide edgewise in said stem portions of the slots as the strips are slid in their respective said cross portions, said pins being inserted in holes in the body plate, nuts for tightening said pins and strips to clamp the pad against the body plate, and abrasive sheets placed over the bottom face and ends of the pad and gripped at the two ends of the body plate in said gripping jaws.

GUSTAF H. EKSTROM.

No references cited. 

